14 C.F.R. § 27.143 Controllability and maneuverability.
Title 14 - Aeronautics and Space
(a) The rotorcraft must be safely controllable and maneuverable— (1) During steady flight; and (2) During any maneuver appropriate to the type, including— (i) Takeoff; (ii) Climb; (iii) Level flight; (iv) Turning flight; (v) Glide; (vi) Landing (power on and power off); and (vii) Recovery to power-on flight from a balked autorotative approach. (b) The margin of cyclic control must allow satisfactory roll and pitch control at V (1) Critical weight; (2) Critical center of gravity; (3) Critical rotor r.p.m.; and (4) Power off (except for helicopters demonstrating compliance with paragraph (e) of this section) and power on. (c) A wind velocity of not less than 17 knots must be established in which the rotorcraft can be operated without loss of control on or near the ground in any maneuver appropriate to the type (such as crosswind takeoffs, sideward flight, and rearward flight), with— (1) Critical weight; (2) Critical center of gravity; (3) Critical rotor r.p.m.; and (4) Altitude, from standard sea level conditions to the maximum altitude capability of the rotorcraft or 7,000 feet, whichever is less. (d) The rotorcraft, after (1) failure of one engine in the case of multiengine rotorcraft that meet Transport Category A engine isolation requirements, or (2) complete engine failure in the case of other rotorcraft, must be controllable over the range of speeds and altitudes for which certification is requested when such power failure occurs with maximum continuous power and critical weight. No corrective action time delay for any condition following power failure may be less than— (i) For the cruise condition, one second, or normal pilot reaction time (whichever is greater); and (ii) For any other condition, normal pilot reaction time. (e) For helicopters for which a V (1) The helicopter must be safely slowed to V (2) At a speed of 1.1 V (Secs. 313(a), 601, 603, 604, and 605 of the Federal Aviation Act of 1958 (49 U.S.C. 1354(a), 1421, 1423, 1424, and 1425); and sec. 6(c) of the Dept. of Transportation Act (49 U.S.C. 1655(c))) [Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as amended by Amdt. 27–2, 33 FR 963, Jan. 26, 1968; Amdt. 27–14, 43 FR 2325, Jan. 16, 1978; Amdt. 27–21, 49 FR 44433, Nov. 6, 1984]
Title 14: Aeronautics and Space
PART 27—AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT
Subpart B—Flight
Flight Characteristics
§ 27.143 Controllability and maneuverability.